FIELD OF THE INVENTION
[0001] A light emitting composite, a light emitting structure, an optical sheet, and an
electronic device are disclosed.
BACKGROUND OF THE INVENTION
[0002] Physical characteristics (e.g., energy bandgaps, melting points, etc.) of nanoparticles
that are known as intrinsic characteristics may be controlled by changing their particle
size, unlike bulk materials. For example, semiconductor nanocrystals, also known as
quantum dots, are supplied with photoenergy or electrical energy and may emit light
in a wavelength corresponding to sizes of the quantum dots. Accordingly, the quantum
dots may be used as a light emitting element emitting light of a particular wavelength
spectrum.
[0003] However, light emitting elements like the quantum dots may be not only agglomerated
with one another in a solvent or a polymer and thus show deteriorated dispersibility,
but also are weak regarding moisture or oxygen and thus may be easily oxidized in
the air. In addition, the light emitting elements like the quantum dots may show low
thermal stability.
SUMMARY OF THE INVENTION
[0004] An embodiment provides a light emitting composite capable of improving dispersibility,
reliability, and thermal stability of a light emitting element.
[0005] Another embodiment provides a light emitting structure including a cured product
of the light emitting composite.
[0006] Yet another embodiment provides an optical sheet including the light emitting structure.
[0007] Still another embodiment provides an electronic device including the light emitting
structure.
[0008] According to an embodiment, a light emitting composite includes a light emitting
element and a three dimensional protection structure bound to the light emitting element
and surrounding the light emitting element. The three dimensional protection structure
includes a SiO
3/2 moiety and a polymerizable functional group.
[0009] In some embodiments, the light emitting element and the three dimensional protection
structure may be bound to each other by -C(=O)NR
a- (wherein R
a is hydrogen or a substituted or unsubstituted C1 to C10 hydrocarbon group).
[0010] In some embodiments, the light emitting element and the three dimensional protection
structure may form a core-shell structure.
[0011] In some embodiments, the three dimensional protection structure may include one of
-C(=O)-, -C(=O)O-, -OC(=O)-, -N(R
b)-C(=O)-, -N(R
b)-C(=O)O-, or-N(R
b)OC(=O)- (wherein R
b is hydrogen or a substituted or unsubstituted C1 to C10 hydrocarbon group), or a
combination thereof.
[0012] In some embodiments, the polymerizable functional group may include one of a (meth)acrylate
group, an epoxy group, a styrene group, an acrylonitrile group, an N-vinylpyrrolidone
group, a vinyl group, a derivative thereof, or a combination thereof.
[0013] In some embodiments, the light emitting composite may be a condensation polymerization
reaction product of a precursor represented by Chemical Formula 1 and a precursor
represented by Chemical Formula 2.

In Chemical Formula 1,
Q is a light emitting element,
L1 is -C(=O)NRa-, wherein Ra is hydrogen or a substituted or unsubstituted C1 to C10 hydrocarbon group,
L2 is one of a single bond, a substituted or unsubstituted C1 to C20 alkylene group,
a substituted or unsubstituted C6 to C30 arylene group, a substituted or unsubstituted
divalent C3 to C30 heterocyclic group, a substituted or unsubstituted C1 to C20 silylene
group, a substituted or unsubstituted siloxane group, or a combination thereof,
R1 to R3 are independently one of a substituted or unsubstituted C1 to C20 alkoxy group, a
hydroxy group, a halogen, or a carboxyl group, and
n is an integer of 1 or more.

In Chemical Formula 2,
L3 and L5 are independently one of a single bond, a substituted or unsubstituted C1 to C20
alkylene group, a substituted or unsubstituted C6 to C30 arylene group, a substituted
or unsubstituted divalent C3 to C30 heterocyclic group, a substituted or unsubstituted
C2 to C20 alkenylene group, a substituted or unsubstituted C2 to C20 alkynylene group,
-Rc-O-Rd-, -Rc-N-Rd-, -Rc-(C=O)-Rd-, or a combination thereof, wherein Rc and Rd are independently a C1 to C10 hydrocarbon group,
L4 is one of -O-, -S-, -(C=O)-, -(C=O)O-, -O(C=O)-, -(C=O)-NRe-,-(C=O)O-NRe-, or -O(C=O)-NRe-, wherein Re is one of hydrogen or a substituted or unsubstituted C1 to C6 hydrocarbon group,
R4 to R6 are independently one of hydrogen, a substituted or unsubstituted C1 to C20 alkyl
group, a substituted or unsubstituted C1 to C20 alkoxy group, a substituted or unsubstituted
C3 to C20 cycloalkyl group, a substituted or unsubstituted C6 to C20 aryl group, a
substituted or unsubstituted C3 to C20 heterocyclic group, a hydroxy group, a halogen,
a carboxyl group, or a combination thereof, provided that at least one of R4 to R6 is one of a substituted or unsubstituted C1 to C20 alkoxy group, a hydroxy group,
a halogen, or a carboxyl group, and
R7 is hydrogen or a methyl group.
[0014] The three dimensional protection structure may be represented by Chemical Formula
3.
[Chemical Formula 3] (R
8R
9R
10SiO
1/2)
M1(R
11R
12SiO
2/2)
D1(R
13SiO
3/2)
T1(SiO
4/2)
Q1
In Chemical Formula 3,
R8 to R13 are independently one of hydrogen, a substituted or unsubstituted C1 to C30 alkyl
group, a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or
unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C7 to C30 arylalkyl
group, a substituted or unsubstituted C1 to C30 heteroalkyl group, a substituted or
unsubstituted C2 to C30 heterocycloalkyl group, a substituted or unsubstituted C2
to C30 alkenyl group, a substituted or unsubstituted C2 to C30 alkynyl group, a substituted
or unsubstituted C1 to C30 alkoxy group, a substituted or unsubstituted C2 to C30
epoxy group, a substituted or unsubstituted C1 to C30 carbonyl group, a substituted
or unsubstituted C1 to C30 carboxyl group, a substituted or unsubstituted amide group,
a hydroxyl group, a (meth)acrylate group, a nitrile group, or a combination thereof,
one of R13's includes a linking point with the light emitting element bound by -C(=O)NRa- (wherein Ra is hydrogen or a substituted or unsubstituted C1 to C10 hydrocarbon group),
at least one of R8 to R13 includes a polymerizable functional group,

and

[0015] In some embodiments, the light emitting element may include one of a quantum dot,
phosphor or a combination thereof.
[0016] In some embodiments, a particle diameter of the light emitting composite may be at
least two times larger than that of the light emitting element.
[0017] According to another embodiment, a light emitting structure includes a cured product
of the light emitting composite.
[0018] In some embodiments, the light emitting structure may further include a cured product
of an organometal compound or a cured product of the light emitting composite and
an organometal compound.
[0019] In some embodiments, the organometal compound may include one of an aluminum compound,
a titanium compound, a zirconium compound, a hafnium compound, a magnesium compound,
a tin compound, or a combination thereof.
[0020] In some embodiments, the light emitting structure may have a weight loss of less
than or equal to about 5% at about 300 °C.
[0021] According to another embodiment, an optical sheet includes the light emitting structure.
[0022] According to another embodiment, an electronic device includes the light emitting
structure.
[0023] In some embodiments, the electronic device may include a light source and a display
panel on the light source.
[0024] In some embodiments, the light emitting structure may be included in the light source.
[0025] In some embodiments, the display panel may include a color conversion layer that
is supplied with first visible light from the light source and emits second visible
light in the same wavelength as the first visible light or in a longer wavelength
than the first visible light, and the light emitting structure may be included in
the color conversion layer.
[0026] In some embodiments, the first visible light may be blue light and the second visible
light may be blue light, green light, red light, or a combination thereof.
[0027] In some embodiments, the electronic device may further include an optical sheet between
the light source and the display panel and the light emitting structure may be included
in the optical sheet.
[0028] In some embodiments, the electronic device may include a first electrode and a second
electrode facing each other and an emission layer between the first electrode and
the second electrode. The emission layer may include the light emitting structure.
[0029] The light emitting composite has improved dispersibility, reliability and thermal
stability and may be effectively applied to a device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030]
FIG. 1 is a schematic view of a light emitting composite according to an embodiment,
FIG. 2 is a schematic cross-sectional view of a liquid crystal display (LCD) including
a color conversion layer according to an embodiment.
FIG. 3 is a cross-sectional view of a light emitting device according to an embodiment,
FIG. 4 is a graph showing a particle diameter distribution of the light emitting composite
obtained in Synthesis Example,
FIG. 5 is a graph showing a particle diameter distribution of the CdTe quantum dot,
and
FIG. 6 is a graph showing weight losses depending on a heat treatment of thin films
according to Example 1 and Comparative Example 1.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0031] Hereinafter, example embodiments of the present disclosure will be described in detail
so that a person skilled in the art would understand the same. This disclosure may,
however, be embodied in many different forms and is not construed as limited to the
example embodiments set forth herein.
[0032] In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated
for clarity. Like reference numerals designate like elements throughout the specification.
It will be understood that when an element such as a layer, film, region, or substrate
is referred to as being "on" another element, it can be directly on the other element
or intervening elements may also be present. In contrast, when an element is referred
to as being "directly on" another element, there are no intervening elements present.
[0033] Hereinafter, 'combination' refers to a mixture of two or more and a stack structure
of two or more.
[0034] As used herein, when a definition is not otherwise provided, "substituted" refers
to replacement of hydrogen of a compound by a substituent selected from a halogen
atom, a hydroxy group, an alkoxy group, a nitro group, a cyano group, an amino group,
an azido group, an amidino group, a hydrazino group, a hydrazono group, a carbonyl
group, a carbamyl group, a thiol group, an ester group, a carboxyl group or a salt
thereof, a sulfonic acid group or a salt thereof, a phosphoric acid or a salt thereof,
a C1 to C20 alkyl group, a C2 to C20 alkenyl group, a C2 to C20 alkynyl group, a C6
to C30 aryl group, a C7 to C30 arylalkyl group, a C1 to C30 alkoxy group, a C1 to
C20 heteroalkyl group, a C3 to C20 heteroaryl group, a C3 to C20 heteroarylalkyl group,
a C3 to C30 cycloalkyl group, C3 to C15 cycloalkenyl group, a C6 to C15 cycloalkynyl
group, a C3 to C30 heterocycloalkyl group, or a combination thereof.
[0035] As used herein, when a definition is not otherwise provided, "hetero" refers to inclusion
of one to three heteroatoms selected from N, O, S, P, and Si.
[0036] Hereinafter, a light emitting composite according to an embodiment is described.
[0037] FIG. 1 is a schematic view of a light emitting composite according to an embodiment.
[0038] Referring to FIG. 1, a light emitting composite 10 according to an embodiment includes
a light emitting element 11 and a protection structure 12 surrounding the light emitting
element 11.
[0039] The light emitting element 11 may be a material stimulated by light or electricity
and itself emitting light in an intrinsic wavelength range and thus include any particle
emitting light at a desired (and/or alternatively predetermined) wavelength without
a particular limit. The light emitting element 11 may be for example a quantum dot,
a phosphor, or a combination thereof.
[0040] For example, the light emitting element 11 may emit light in at least one part wavelength
region of a visible ray region, for example blue light, red light, green light, or
combined light thereof. Herein, the blue light may have for example a peak emission
wavelength (λ
peak) in a wavelength region of about 430 nm to about 470 nm, the red light may have for
example a peak emission wavelength (λ
peak) in a wavelength region of about 620 nm to about 660 nm, and the green light may
have for example a peak emission wavelength (λ
peak) in a wavelength region of about 510 nm to about 550 nm.
[0041] For example, the light emitting element 11 may have for example a particle diameter
(an average largest particle diameter (length) for a non-spherical shape) of about
1 nm to about 80 nm, about 1 nm to about 50 nm, about 1 nm to about 40 nm, about 1
nm to about 30 nm, or about 1 nm to about 20 nm.
[0042] For example, the light emitting element 11 may be a quantum dot. The quantum dot
may be a semiconductor nanocrystal in a general concept, and may have various shapes,
for example an isotropic semiconductor nanocrystal, a quantum rod, and a quantum plate.
[0043] The quantum dot may be for example a Group II-VI semiconductor compound, a Group
III-V semiconductor compound, a Group IV-VI semiconductor compound, a Group IV semiconductor
compound, a Group I-III-VI semiconductor compound, a Group I-II-IV-VI semiconductor
compound, a Group II-III-V semiconductor compound, or a combination thereof. The Group
II-VI semiconductor compound may be for example selected from a binary element compound
selected from CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS, and a
mixture thereof; a ternary element compound selected from CdSeS, CdSeTe, CdSTe, ZnSeS,
ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe,
HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS, and a mixture thereof; and a quaternary element
compound selected from HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe,
HgZnSeS, HgZnSeTe, HgZnSTe, and a mixture thereof, but is not limited thereto. The
Group III-V semiconductor compound may be for example selected from a binary element
compound selected from GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs,
InSb, and a mixture thereof; a ternary element compound selected from GaNP, GaNAs,
GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs,
InPSb, GaAlNP, and a mixture thereof; and a quaternary element compound selected from
GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP,
InAlNAs, InAlNSb, InAlPAs, InAlPSb, and a mixture thereof, but is not limited thereto.
The Group IV-VI semiconductor compound may be for example selected from a binary element
compound selected from SnS, SnSe, SnTe, PbS, PbSe, PbTe, and a mixture thereof; a
ternary element compound selected from SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe,
SnPbS, SnPbSe, SnPbTe, and a mixture thereof; and a quaternary element compound selected
from SnPbSSe, SnPbSeTe, SnPbSTe, and a mixture thereof, but is not limited thereto.
The Group IV semiconductor compound may be for example selected from a singular element
semiconductor compound selected from Si, Ge, and a mixture thereof; and a binary element
semiconductor compound selected from SiC, SiGe, and a mixture thereof, but is not
limited thereto. The Group I-III-VI semiconductor compound may be for example selected
from CuInSe
2, CuInS
2, CuInGaSe, CuInGaS, and a mixture thereof, but is not limited thereto. The Group
I-II-IV-VI semiconductor compound may be for example selected from CuZnSnSe and CuZnSnS,
but is not limited thereto. The Group II-III-V semiconductor compound may include
for example InZnP, but is not limited thereto.
[0044] The quantum dot may have a core-shell structure including a core and a shell. For
example, since a material composition of the shell of the quantum dot may have a higher
energy bandgap than a material composition of the core of the quantum dot, the quantum
dot may have a quantum confinement effect and thus emit light. For example, the shell
of the quantum dot may be a monolayer or a multi-layer, and for example shells of
the multi-layer, a shell that is far from the core may have a higher energy bandgap
than a shell that is near to the core, and thereby the quantum dot may exhibit a quantum
confinement effect. The material forming the core of the quantum dot may be different
from the material forming the shell of the quantum dot, and these materials may be
respectively selected from the above semiconductor compounds as long as the quantum
confinement effect is obtained.
[0045] The light emitting element 11 may have a plurality of reaction sites capable of causing
a condensation reaction on the surface, and the reaction sites may be for example
hydrophilic reaction sites, for example, a carboxyl group and/or an amide group. The
reaction sites such as the carboxyl group and/or the amide group may be obtained through
a hydrophilic surface treatment of the light emitting element 11.
[0046] The light emitting element 11 is surrounded with a protection structure 12 and forms
a three-dimensional structure, for example, both the light emitting element 11 and
the protection structure 12 may form a core-shell structure. The protection structure
12 may include a plurality of a polymer chains including an organic/inorganic hybrid
material, and each polymer chain is bound to the surface of the light emitting element
11. For example, the light emitting element 11 and the protection structure 12 are
bound to each other by * -C(=O)NR
a- * (wherein R
a is hydrogen or a substituted or unsubstituted C1 to C10 hydrocarbon group), wherein
one * may be a binding point on the surface of the light emitting element 11, and
another * may be a binding point of a polymer chain of the protection structure 12.
[0047] For example, each polymer of the protection structure 12 may be polyorganosiloxane,
for example, polyorganosiloxane having a three dimensional structure having a SiO
3/2 moiety. The polyorganosiloxane having a three dimensional structure may have a polymerizable
functional group at the terminal end, and the polymerizable functional group may be
for example a (meth)acrylate group, an epoxy group, a styrene group, an acrylonitrile
group, an N-vinylpyrrolidone group, a vinyl group, a derivative thereof, or a combination
thereof, but is not limited thereto. The polymerizable functional group may form a
dense network structure through photocuring and/or thermal curing during the formation
of a thin film.
[0048] For example, each polymer of the protection structure 12 may include-C(=O)-, -C(=O)O-,
-OC(=O)-, -N(R
b)-C(=O)-, -N(R
b)-C(=O)O-, -N(R
b)OC(=O)-(wherein R
b is hydrogen or a substituted or unsubstituted C1 to C10 hydrocarbon group), or a
combination thereof in its structure.
[0049] For example, each polymer of the protection structure 12 may be represented by Chemical
Formula 3.
[Chemical Formula 3] (R
8R
9R
10SiO
1/2)
M1(R
11R
12SiO
2/2)
D1(R
13SiO
3/2)
T1(SiO
4/2)
Q1
In Chemical Formula 3,
R8 to R13 are independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group,
a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or unsubstituted
C6 to C30 aryl group, a substituted or unsubstituted C7 to C30 arylalkyl group, a
substituted or unsubstituted C1 to C30 heteroalkyl group, a substituted or unsubstituted
C2 to C30 heterocycloalkyl group, a substituted or unsubstituted C2 to C30 alkenyl
group, a substituted or unsubstituted C2 to C30 alkynyl group, a substituted or unsubstituted
C1 to C30 alkoxy group, a substituted or unsubstituted C2 to C30 epoxy group, a substituted
or unsubstituted C1 to C30 carbonyl group, a substituted or unsubstituted C1 to C30
carboxyl group, a substituted or unsubstituted amide group, a hydroxyl group, a (meth)acrylate
group, a nitrile group, or a combination thereof,
one of R13's includes a linking point with the light emitting element bound by -C(=O)NRa- (wherein Ra is hydrogen or a substituted or unsubstituted C1 to C10 hydrocarbon group),
at least one of R8 to R13 includes a polymerizable functional group,

and

[0050] For example, at least one of R
8 to R
13 of Chemical Formula 3 may include a polymerizable functional group and the polymerizable
functional group may include for example a (meth)acrylate group, an epoxy group, a
styrene group, an acrylonitrile group, an N-vinylpyrrolidone group, a vinyl group,
a derivative thereof, or a combination thereof.
[0051] For example, at least one of R
8 to R
13 of Chemical Formula 3 may include-C(=O)-, -C(=O)O-, -OC(=O)-, -N(R
b)-C(=O)-, -N(R
b)-C(=O)O-, -N(R
b)OC(=O)-(wherein R
b is hydrogen or a substituted or unsubstituted C1 to C10 hydrocarbon group), or a
combination thereof.
[0052] For example, the light emitting composite 10 may be a condensation polymerization
reaction product obtained through a reaction of precursors of organic/inorganic hybrid
monomers and/or organic/inorganic hybrid oligomers, for example, through a reaction
of a siloxane precursor which is a reaction product of the hydrophilic light emitting
element 11 in a sol state and at least one silicon monomer, and another siloxane precursor
having a polymerizable functional group.
[0053] The silicon monomer may be for example a substituted or unsubstituted silane monomer,
for example at least one monomer represented by R
aR
bR
cSiZ
1, at least one monomer represented by R
dR
eSiZ
2Z
3, at least one monomer represented by R
fSiZ
4Z
5Z
6, and/or at least one monomer represented by SiZ
7Z
8Z
9Z
10. Herein, R
a to R
f are independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group,
a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or unsubstituted
C6 to C30 aryl group, a substituted or unsubstituted C7 to C30 arylalkyl group, a
substituted or unsubstituted C1 to C30 heteroalkyl group, a substituted or unsubstituted
C2 to C30 heterocycloalkyl group, a substituted or unsubstituted C2 to C30 alkenyl
group, a substituted or unsubstituted C2 to C30 alkynyl group, a substituted or unsubstituted
C1 to C30 alkoxy group, a substituted or unsubstituted C2 to C30 epoxy group, a substituted
or unsubstituted C1 to C30 carbonyl group, a hydroxy group, or a combination thereof,
and Z
1 to Z
10 are independently C1 to C6 alkoxy group, a hydroxy group, a halogen, a carboxyl group
or a combination thereof. For example, one of R
a to R
f may be a C1 to C20 alkyl group substituted with an amino group or a carboxyl group.
[0054] The condensation polymerization reaction product may be condensation-polymerized
and bonded with the hydrophilic light emitting element 11 and simultaneously, form
polyorganosiloxane having a three dimensional structure through a hydrolysis and a
condensation polymerization among the silicon monomers.
[0055] For example, the light emitting composite 10 may be a condensation polymerization
reaction product of a precursor represented by Chemical Formula 1 and a precursor
represented by Chemical Formula 2.

In Chemical Formula 1,
Q is a light emitting element,
L1 is -C(=O)NRa-, wherein Ra is hydrogen or a substituted or unsubstituted C1 to C10 hydrocarbon group,
L2 is a single bond, a substituted or unsubstituted C1 to C20 alkylene group, a substituted
or unsubstituted C6 to C30 arylene group, a substituted or unsubstituted divalent
C3 to C30 heterocyclic group, a substituted or unsubstituted C1 to C20 silylene group,
a substituted or unsubstituted siloxane group, or a combination thereof,
R1 to R3 are independently a substituted or unsubstituted C1 to C20 alkoxy group, a hydroxy
group, a halogen, or a carboxyl group, and
n is an integer of 1 or more.

In Chemical Formula 2,
L3 and L5 are independently a single bond, a substituted or unsubstituted C1 to C20 alkylene
group, a substituted or unsubstituted C6 to C30 arylene group, a substituted or unsubstituted
divalent C3 to C30 heterocyclic group, a substituted or unsubstituted C2 to C20 alkenylene
group, a substituted or unsubstituted C2 to C20 alkynylene group, -Rc-O-Rd-, -Rc-N-Rd-, -Rc-(C=O)-Rd-, or a combination thereof, wherein Rc and Rd are independently a C1 to C10 hydrocarbon group,
L4 is -O-, -S-, -(C=O)-, -(C=O)O-, -O(C=O)-, -(C=O)-NRe-, -(C=O)O-NRe-, or -O(C=O)-NRe-, wherein Re is hydrogen or a substituted or unsubstituted C1 to C6 hydrocarbon group,
R4 to R6 are independently hydrogen, a substituted or unsubstituted C1 to C20 alkyl group,
a substituted or unsubstituted C1 to C20 alkoxy group, a substituted or unsubstituted
C3 to C20 cycloalkyl group, a substituted or unsubstituted C6 to C20 aryl group, a
substituted or unsubstituted C3 to C20 heterocyclic group, a hydroxy group, a halogen,
a carboxyl group, or a combination thereof, provided that at least one of R4 to R6 is a substituted or unsubstituted C1 to C20 alkoxy group, a hydroxy group, a halogen,
or a carboxyl group, and
R7 is hydrogen or a methyl group.
[0056] For example, the precursor represented by Chemical Formula 1 may be represented by
Chemical Formula 1a or 1b.

In Chemical Formula 1a or 1b,
Q is a light emitting element,
L2 is a single bond, a substituted or unsubstituted C1 to C20 alkylene group, a substituted
or unsubstituted C6 to C30 arylene group, a substituted or unsubstituted divalent
C3 to C30 heterocyclic group, a substituted or unsubstituted C1 to C20 silyl group,
a substituted or unsubstituted siloxane group, or a combination thereof,
R1a to R3a are independently hydrogen or a substituted or unsubstituted C1 to C20 alkyl group,
n is an integer of 1 or more.
[0057] For example, the precursor represented by Chemical Formula 2 may be represented by
Chemical Formula 2a.

In Chemical Formula 2a,
L3 and L5 are independently a single bond, a substituted or unsubstituted C1 to C20 alkylene
group, a substituted or unsubstituted C6 to C30 arylene group, a substituted or unsubstituted
divalent C3 to C30 heterocyclic group, a substituted or unsubstituted C2 to C20 alkenylene
group, a substituted or unsubstituted C2 to C20 alkynylene group, -Rc-O-Rd-, -Rc-N-Rd-, -Rc-(C=O)-Rd-, or a combination thereof, wherein Rc and Rd are independently a C1 to C10 hydrocarbon group, and
R4a to R6a are independently hydrogen or a substituted or unsubstituted C1 to C20 alkyl group.
[0058] A particle diameter of the light emitting composite 10 may have at least about 1.5
times, for example at least about 2 times larger than that of the light emitting element
11.
[0059] The light emitting composite 10 may be cured by heat and/or light and thus form a
light emitting structure. The light emitting structure may include a cured product
of the above light emitting composite 10 and be included in a thin film, a sheet,
a film, or a device requiring a light emission.
[0060] The light emitting structure may be obtained by coating a composition including the
above light emitting composite 10 and curing it.
[0061] The composition may include for example the light emitting composite 10, a cross-linking
agent, a cross-linking auxiliary agent, and a solvent or a polymer.
[0062] The light emitting composite 10 is the same as described above.
[0063] The cross-linking agent may be for example a photo-cross-linking agent and/or a thermal
cross-linking agent, and herein, the photo-cross-linking agent may be for example
a (meth)acrylate compound like pentaerythritoltriacrylate, and the thermal cross-linking
agent may be for example an ether compound such as trimethylopropanetriglycidylether,
1,4-butanedioldivinylether, tri(ethylene glycol)divinylether, trimethylolpropanetrivinylether,
or 1,4-cyclohexanedimethanoldivinylether or a combination thereof, but is not limited
thereto.
[0064] The cross-linking agent may be included in an amount of about 0.1 to 50 parts by
weight, for example, in an amount of about 10 to 50 parts by weight based on 100 parts
by weight of the light emitting composite 10.
[0065] The cross-linking auxiliary agent may be, for example, a photo-cross-linking auxiliary
agent and/or a thermal cross-linking auxiliary agent, for example, a polymer and/or
an organometal compound. The cross-linking auxiliary agent may be for example an organometallic
compound such as an aluminum compound, a titanium compound, a zirconium compound,
a hafnium compound, a magnesium compound, a tin compound, or a combination thereof,
for example, aluminum acetoacetate but is not limited thereto.
[0066] The cross-linking agent may be included in an amount of about 0.1 to 30 parts by
weight, for example, in an amount of about 1 to 20 parts by weight based on 100 parts
by weight of the light emitting composite 10.
[0067] The composition may further include a reaction initiator, a photoacid generator,
and/or a dispersing agent.
[0068] The solvent is not particularly limited as long as it may dissolve or disperse the
above components, but may be for example an aliphatic hydrocarbon solvent such as
hexane, and the like; an aromatic hydrocarbon solvent such as mesitylene, xylene,
and the like; a ketone based solvent such as cyclohexanone, methylisobutylketone,
1-methyl-2-pyrrolidinone, acetone, and the like; an ether based solvent such as anisole,
tetrahydrofuran, isopropylether, and the like; an acetate based solvent such as ethylacetate,
butylacetate, propylene glycolmethyletheracetate, and the like; an alcohol based solvent
such as isopropylalcohol, butanol, and the like; an amide based solvent such as dimethyl
acetamide, dimethyl formamide, and the like; a silicon-based solvent, or a combination
thereof.
[0069] The solvent may be included in a balance amount except for the above components,
and a total amount of a solid in the composition except for the solvent and may be
included in an amount of about 5 wt% to about 80 wt%, for example, about 5 wt% to
about 50 wt%.
[0070] The polymer may be a matrix dispersing the light emitting composite 10, for example,
a transparent polymer. The polymer may be for example polyvinylpyrrolidone, polystyrene,
polyethylene, polypropylene, poly(methyl)acrylate, polymethylmethacrylate, polybutylmethacrylate
(PBMA), a copolymer thereof, or a combination thereof, but is not limited thereto.
[0071] The composition may be coated on a substrate or a lower layer and cured into a light
emitting structure. Herein, the coating may be for example spin coating, slit coating,
bar coating, Inkjet printing, and/or the like, and the curing may be for example photocuring
and/or thermal curing.
[0072] The light emitting element 11 is three dimensionally surrounded with the organic/inorganic
hybrid protection structure 12 and thus may be suppressed from agglomeration in the
solvent or polymer and accordingly, increase dispersion and simultaneously, be effectively
protected from moisture or oxygen.
[0073] The light emitting structure may include a cured product of the above light emitting
composite 10, and the light emitting structure may further include a cross-linking
agent and/or a cured product of a cross-linking auxiliary agent.
[0074] The light emitting structure is obtained by curing the light emitting composite including
a light emitting element and an organic/inorganic hybrid protection structure to form
a three dimensional network structure and much effectively protect the light emitting
element ad thus increase thermal/optical and/or electrical stability of the light
emitting structure.
[0075] For example, the light emitting structure, a cured product of the light emitting
composite 10, may have higher thermal stability than a light emitting element having
no protection structure, for example, a weight loss of less than or equal to about
10% at about 300 °C, a weight loss of less than or equal to about 7 % at about 300
°C, a weight loss of less than or equal to about 5 % at about 300°C, or a weight loss
of less than or equal to about 3 % at about 300 °C.
[0076] The light emitting structure may be applied to various fields.
[0077] For example, the light emitting structure may be applied to an optical sheet. The
optical sheet may receive light in a desired (and/or alternatively predetermined)
wavelength region and emit light in the same region or in other wavelength regions.
[0078] For example, the light emitting structure may be applied to a light source. The light
source including the light emitting structure may supply light in a desired (and/or
alternatively predetermined) light wavelength spectrum.
[0079] For example, the light emitting structure may be applied to a color conversion layer.
The color conversion layer may receive light in a first visible ray region and emit
light in the same region as the first visible ray region or light in a second visible
ray region differing therefrom.
[0080] The optical sheet, the light source, and/or the color conversion layer may be applied
to various electronic devices, for example various display devices. The display device
may be for example a liquid crystal display (LCD) or an organic light emitting diode
device.
[0081] FIG. 2 is a schematic cross-sectional view of a liquid crystal display (LCD) according
to an embodiment.
[0082] Referring to FIG. 2, a liquid crystal display (LCD) 400 according to an embodiment
includes a light source 40 and a liquid crystal display panel 300.
[0083] The light source 40 may be a planar light source, a dot light source, or a line light
source that supplies light with the liquid crystal panel 300, and may be for example
disposed in form of an edge-type or a direct type. The light source 40 may include
a light emitting region including a light emitting body, a reflector disposed under
the light emitting region and reflecting light emitted from the light emitting region,
a light guide that supplies the light emitted from the light emitting region toward
a liquid crystal panel and/or at least one optical sheet disposed on the light guide,
but is not limited thereto.
[0084] The light emitting body may be, for example a fluorescent lamp or a light emitting
diode (LED), and for example may supply light in a visible ray region (hereinafter,
referred to as 'visible light'), for example blue light having high energy.
[0085] For example, the light emitting body may include the light emitting structure. For
example, the optical sheet may include the light emitting structure.
[0086] The liquid crystal display panel 300 includes a lower display panel 100 disposed
on the light source 40, an upper display panel 200 facing the lower display panel
100, and a liquid crystal layer 3 disposed between the lower display panel 100 and
the upper display panel 200.
[0087] The lower display panel 100 includes a lower substrate 110, a plurality of wires
(not shown), a thin film transistor Q, a pixel electrode 191, and an alignment layer
11.
[0088] The lower substrate 110 may be, for example, an insulation substrate such as a glass
substrate or a polymer substrate, and the polymer substrate may be made of, for example
polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyacrylate,
polyimide, or a combination thereof, but is not limited thereto.
[0089] A plurality of gate lines (not shown) that supplies a gate signal and a plurality
of data line (not shown) that supplies a data signal may be formed while crossing
each other on the lower substrate 110, and a plurality of pixels PX are arranged in
a form of a matrix defined by the gate lines and the data lines.
[0090] A plurality of thin film transistors Q are formed on the lower substrate 110. The
thin film transistors Q may include a gate electrode (not shown) connected to the
gate lines, a semiconductor (not shown) overlapping with the gate electrode, a gate
insulating layer (not shown) disposed between the gate electrode and the semiconductor,
a source electrode (not shown) connected to the data lines, and a drain electrode
(not shown) facing the the source electrode in the center of the semiconductor. In
FIG. 2, each pixel PX includes one thin film transistor Q, but is not limited thereto,
and two or more thin film transistors may be disposed.
[0091] A protective layer 180 is formed on the thin film transistors Q, and the protective
layer 180 has a contact hole 185 exposing the thin film transistors Q.
[0092] A pixel electrode 191 is formed on the protective layer 180. The pixel electrode
191 may be made of a transparent conductor such as ITO or IZO, and is electrically
connected to the thin film transistor Q through the contact hole 185. The pixel electrode
191 may have a desired (and/or alternatively predetermined) pattern.
[0093] An alignment layer 11 is formed on the pixel electrode 191.
[0094] The upper display panel 200 includes an upper substrate 210, a color conversion layer
230, a common electrode 270, and an alignment layer 21.
[0095] The upper substrate 210 may be, for example, an insulation substrate such as a glass
substrate or a polymer substrate, and the polymer substrate may be made of, for example
polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyacrylate,
polyimide, or a combination thereof, but is not limited thereto.
[0096] A light blocking member 220 that is referred to as a black matrix is formed on one
surface of the upper substrate 210. The light blocking member 220 may block light
leakage between the pixel electrodes 191.
[0097] In addition, a color conversion layer 230 is formed on one surface of the upper substrate
210. The color conversion layer 230 is supplied with light in a desired (and/or alternatively
predetermined) wavelength region and emits the same light or light in a different
wavelength region to display colors. The color conversion layer 230 may include the
light emitting structure (e.g., a cured product of the light emitting composite 10
in FIG. 1).
[0098] For example, the light emitting structure included in the color conversion layer
230 may emit light in the same wavelength region supplied from the light source 40
or light in a longer wavelength region. For example, when the light source 40 supplies
blue light, the light emitting structure included in the color conversion layer 230
may emit blue light in the same wavelength region or emit light in a longer wavelength
region than blue light, for example red light or green light.
[0099] In this way, high photoconversion efficiency and low power consumption may be realized
by including the color conversion layer 230 including the light emitting structure.
In addition, the color conversion layer 230 including the light emitting structure
may much reduce a light loss according to the absorption and thus increase photoefficiency
compared with a conventional color filter including a dye and/or a pigment and thus
absorbing a considerable dose of light emitted from the light source 40 and showing
low photoefficiency. In addition, color purity may be increased by an inherent luminous
color of the light emitting element. Furthermore, the light emitting element emits
light scattering in all directions and may improve viewing angle characteristics.
In addition, as described above, the light emitting structure has higher thermal stability
than a quantum dot or a phosphor and thus may limit and/or prevent degradation of
the color conversion layer 230 due to heat during the process and/or the operation.
[0100] FIG. 2 shows a red conversion layer 230R including a red light emitting structure
emitting red light, a green conversion layer 230G including a green light emitting
structure emitting green light, and a blue conversion layer 230B including a blue
light emitting structure emitting blue light, but the present disclosure is not limited
thereto. For example, the red conversion layer 230R may emit light in a wavelength
region ranging from greater than about 590 nm to less than or equal to about 700 nm,
the green conversion layer 230G may emit light in a wavelength region ranging from
about 510 nm to about 590 nm, and the blue conversion layer 230B may emit light in
a wavelength region ranging from greater than or equal to about 380 nm to less than
about 510 nm. For example, the light emitting structure may be for example a light
emitting structure emitting cyan light, a light emitting structure emitting magenta
light, and/or a light emitting structure emitting yellow light, or additionally include
these light emitting structures. For example, when the light source 40 supplies blue
light, the blue conversion layer 230B passes the light supplied from the light source
40 without a separate light emitting element as it is and thus display blue, and herein,
the blue conversion layer 230B may be empty or include a transparent insulator.
[0101] The common electrode 270 is formed on one surface of the color conversion layer 230.
The common electrode 270 may be, for example made of a transparent conductor such
as ITO or IZO and formed on a whole surface of the upper phase difference layer 250.
The common electrode 270 has a desired (and/or alternatively predetermined) pattern.
[0102] The alignment layer 21 is coated on one surface of the common electrode 270.
[0103] The liquid crystal layer 3 including a plurality of liquid crystals 30 is disposed
between the lower display panel 100 and the upper display panel 200. The liquid crystal
30 may have positive or negative dielectric anisotropy. For example, the liquid crystal
30 may have negative dielectric anisotropy. For example, the liquid crystal 30 may
be aligned in a substantially vertical direction to the surfaces of the substrates
110 and 210 when an electric field is not applied to the pixel electrode 191 and the
common electrode 270. Thereby the liquid crystal display 500 may realize a vertical
alignment liquid crystal display.
[0104] For example, the light emitting structure may be applied to a light emitting device.
[0105] FIG. 3 is a cross-sectional view of a light emitting device according to an embodiment.
[0106] Referring to FIG. 3, a light emitting device 500 according to an embodiment includes
an anode 510 and a cathode 520 facing each other and an emission layer 530 disposed
between the anode 510 and the cathode 520.
[0107] A substrate (not shown) may be disposed on a surface of the anode 510 or on a surface
of the cathode 520. The substrate may be for example made of an inorganic material
such as glass; an organic material such as polycarbonate, polymethylmethacrylate,
polyethyleneterephthalate, polyethylenenaphthalate, polyamide, polyethersulfone, or
a combination thereof; or a silicon wafer.
[0108] The anode 510 may be made of a conductor having a relatively large work function
to help hole injection, and may be for example a metal, a conductive metal oxide,
or a combination thereof. The anode 510 may be for example made of a metal or an alloy
thereof such as nickel, platinum, vanadium, chromium, copper, zinc, or gold; a conductive
metal oxide such as zinc oxide, indium oxide, tin oxide, indium tin oxide (ITO), indium
zinc oxide (IZO), or a fluorine-doped tin oxide; or a combination of metal and oxide
such as ZnO and Al or SnO
2 and Sb, but is not limited thereto.
[0109] The cathode 520 may be for example made of a conductor having relatively low work
function conductor to help electron injection and may be for example made of a metal,
a conductive metal oxide, and/or a conductive polymer. The cathode 520 may be for
example a metal or an alloy thereof such as magnesium, calcium, sodium, potassium,
titanium, indium, yttrium, lithium, gadolinium, aluminum silver, tin, lead, cesium,
or barium; a multi-layer structure material such as LiF/Al, LiO
2/Al, LiF/Ca, Liq/Al, and BaF
2/Ca, but is not limited thereto.
[0110] At least one of the anode 510 and the cathode 520 may be a light-transmitting electrode
and the light-transmitting electrode may be for example made of a conductive oxide
such as a zinc oxide, indium oxide, tin oxide, indium tin oxide (ITO), indium zinc
oxide (IZO), or fluorine doped tin oxide, or a metal thin layer of a single layer
or a multilayer. When one of the anode 510 and the cathode 520 is a non-light-transmitting
electrode, it may be made of for example an opaque conductor such as aluminum (Al),
silver (Ag), or gold (Au).
[0111] The emission layer 530 may include the light emitting structure.
[0112] A charge auxiliary layer (not shown) may be further disposed between the anode 510
and the emission layer 530 and/or between the cathode 520 and the emission layer 530,
for example a hole injection layer (HIL), a hole transport layer (HTL) and/or an electron
blocking layer between the anode 510 and the emission layer 530 and an electron injection
layer (EIL), an electron transport layer (ETL) and/or a hole blocking layer between
the cathode 520 and the emission layer 530.
[0113] Hereinafter, the embodiments are illustrated in more detail with reference to examples.
However, these examples are non-limiting examples, and the present disclosure is not
limited thereto.
Synthesis Examples
Synthesis Example 1: Synthesis of Compound 1
[0114]

[0115] 50 mg (0.2 mmol) of a COOH functionalized Cd-Te Quantum dot is added to 10 ml of
ethanol, a small amount of p-toluene sulfonic acid as a catalyst is added thereto,
and the mixture is refluxed for 24 hours. Subsequently, the reaction solution is cooled
down and filtered to obtain 50 mg of Compound 1.
Synthesis Example 2: Synthesis of Compound 2
[0116]

[0117] Compound 1 (50 mg, 0.2 mmol) is suspended in 10 ml of THF, and 3-aminopropyltrimethoxy
silane (36 mg, 0.2 mmol) and ZrCl
2 (5 mg, 0.002 mol) are added thereto. Subsequently, the obtained mixture is refluxed
for 24 hours, then, cooled down and refluxed, and filtered to obtain Compound 2.
Synthesis Example 3: Synthesis of Compound 4
[0118]

[0119] 5 g of methylalcohol is put in a reactor equipped with a reflux-cooler and made of
a glass material, Compound 2 (0.5 g, 1.1 mmol) and Compound 3 (0.4 g, 1.1 mmol) that
is a silane compound are added thereto, and the obtained mixture is stirred at room
temperature for 1 hour. Then, 0.08 g of a hydrochloric acid aqueous solution having
a concentration of 0.1 N is slowly added thereto in a dropwise fashion and the obtained
mixture is additionally stirred at room temperature for 2 hour to induce a hydrolysis
reaction. Subsequently, the reactant is heated up to 80 °C and further reacted for
condensation and polymerization for 36 hours to obtain a light emitting composite
(Compound 4).
[0120] The obtained light emitting composite has a weight average molecular weight of 2000,
a polydispersity index (PDI) of 1.9, and pH 7 when measured in a GPC method. Subsequently,
10 g of propylene glycol monomethyl ether acetate is added to the light emitting composite
to dilute it, and the diluted resultant is distilled under a reduced pressure and
a condition of 60 cm Hg and 60 °C to remove a byproduct and obtain a light emitting
composite dispersed in propylene glycol monomethyl ether aceta.
Evaluation I
[0121] A particle diameter distribution of the light emitting composite according to Synthesis
Example is compared with that of a CdTe quantum dot.
[0122] The particle diameter distributions of the light emitting composite according to
Synthesis Example and the CdTe quantum dot are evaluated by using SAXpace (Anton Paar).
[0123] FIG. 4 is a graph showing a particle diameter distribution of the light emitting
composite obtained in Synthesis Example, and FIG. 5 is a graph showing a particle
diameter distribution of the CdTe quantum dot.
[0124] Referring to FIGS. 4 and 5, the light emitting composite of Synthesis Example turns
out to have a wider particle diameter distribution than the CdTe quantum dot. Specifically,
the light emitting composite according to Synthesis Example has a particle diameter
distribution of about 0 nm to 16 nm, but the CdTe quantum dot has a particle diameter
distribution of about 0 nm to 5.7 nm.
[0125] Accordingly, the CdTe quantum dot is surrounded with a protection structure and thus
formed into the light emitting composite.
Preparation Examples
Preparation Example 1
[0126] A composition is prepared by respectively adding 1 wt% of aluminum acetoacetate and
1 wt% of a photoinitiator (Igacure, BASF) to the light emitting composite according
to Synthesis Example based on a total weight of the light emitting composite, propylene
glycol monomethyl ether acetate is added thereto to adjust a concentration of the
mixture into 35 wt%, and the obtained mixture is mixed with a ball mill for 1 hour
to prepare a composition.
Comparative Preparation Example 1
[0127] A composition is prepared according to the same method as Preparation Example 1 except
for using a CdTe quantum dot instead of the light emitting composite according to
Synthesis Example.
Formation of Thin Film
Example 1
[0128] The composition according to Preparation Example 1 is spin-coated on a glass substrate,
pre-cured (pre-annealed) at 100 °C for 10 minutes, and cured for 8 minutes by using
200W high pressure mercury lamp having a wavelength region of 240 nm to 400 nm to
form a thin film. And then post-cured at 220°C for 1hr.
Comparative Example 1
[0129] A thin film is formed according to the same method as Example 1 except for coating
the composition according to Comparative Preparation Example 1 instead of the composition
according to Preparation Example 1.
Evaluation II
[0130] Thermal stability of the thin films according to Example 1 and Comparative Example
1 are evaluated.
[0131] The thermal stability is evaluated by using a thermogravimetric analyzer (TA instrument,
Discovery).
[0132] The results are shown in FIG. 6.
[0133] FIG. 6 is a graph showing weight losses of the thin films according to Example 1
and Comparative Example 1 depending on a heat treatment.
[0134] Referring to FIG. 6, the thin film according to Example 1 has a less weight loss
depending on a heat treatment than the thin film according to Comparative Example
1. Specifically, the thin film of Example 1 has a weight loss of about 1.5 wt% at
about 150 °C, the thin film of Comparative Example 1 has a weight loss of about 8.8
wt%, and the thin film of Example 1 has a weight loss of about 3.4 wt% at about 300
°C, but the thin film of Comparative Example 1 has a weight loss of about 14 wt%.
Accordingly, the thin film of Example 1 showed higher thermal stability than the thin
film of Comparative Example 1.
Evaluation III
[0135] Photoluminescence characteristics of the thin film of Example 1 are evaluated.
[0136] The photoluminescence characteristics are evaluated by using a fluorescence spectrophotometer
(F-7000, Hitachi Ltd.).
[0137] The thin film of Example 1 has a peak emission wavelength as shown in Table 1.
(Table 1)
|
Peak emission wavelength (λpeak) |
Full width at half maximum (FWHM) (nm) |
Example 1 |
560 nm |
50 nm |
[0138] Referring to Table 1, the thin film of Example 1 has sufficient photoluminescence
characteristics.
[0139] While this disclosure has been described in connection with what is presently considered
to be practical example embodiments, it is to be understood that the invention is
not limited to the disclosed embodiments, but, on the contrary, is intended to cover
various modifications and equivalent arrangements included within the scope of the
appended claims.
1. A light emitting composite, comprising
a light emitting element, and
a three dimensional protection structure bound to the light emitting element, and
surrounding the light emitting element,
wherein the three dimensional protection structure comprises a SiO3/2 moiety and a polymerizable functional group.
2. The light emitting composite of claim 1, wherein
the light emitting element and the three dimensional protection structure are bound
to each other by -C(=O)NRa- (wherein Ra is hydrogen or a substituted or unsubstituted C1 to C10 hydrocarbon group); and/or
wherein the light emitting element and the three dimensional protection structure
form a core-shell structure.
3. The light emitting composite of claims 1 or 2, wherein the three dimensional protection
structure includes one of -C(=O)-, -C(=O)O-, -OC(=O)-,-N(Rb)-C(=O)-, -N(Rb)-C(=O)O-, -N(Rb)OC(=O)- (wherein Rb is hydrogen or a substituted or unsubstituted C1 to C10 hydrocarbon group), or a
combination thereof; and/or
wherein the polymerizable functional group includes one of a (meth)acrylate group,
an epoxy group, a styrene group, an acrylonitrile group, an N-vinylpyrrolidone group,
a vinyl group, a derivative thereof, or a combination thereof.
4. The light emitting composite of any of claims 1-3, wherein the light emitting composite
is a condensation polymerization reaction product of a precursor represented by Chemical
Formula 1 and a precursor represented by Chemical Formula 2:

wherein, in Chemical Formula 1,
Q is a light emitting element,
L1 is -C(=O)NRa-, wherein Ra is hydrogen or a substituted or unsubstituted C1 to C10 hydrocarbon group,
L2 is one of a single bond, a substituted or unsubstituted C1 to C20 alkylene group,
a substituted or unsubstituted C6 to C30 arylene group, a substituted or unsubstituted
divalent C3 to C30 heterocyclic group, a substituted or unsubstituted C1 to C20 silylene
group, a substituted or unsubstituted siloxane group, or a combination thereof,
R1 to R3 are independently one of a substituted or unsubstituted C1 to C20 alkoxy group, a
hydroxy group, a halogen, or a carboxyl group, and
n is an integer of 1 or more,

wherein, in Chemical Formula 2,
L3 and L5 are independently one of a single bond, a substituted or unsubstituted C1 to C20
alkylene group, a substituted or unsubstituted C6 to C30 arylene group, a substituted
or unsubstituted divalent C3 to C30 heterocyclic group, a substituted or unsubstituted
C2 to C20 alkenylene group, a substituted or unsubstituted C2 to C20 alkynylene group,
-Rc-O-Rd-, -Rc-N-Rd-, -RC-(C=O)-Rd-, or a combination thereof, wherein Rc and Rd are independently a C1 to C10 hydrocarbon group,
L4 is one of -O-, -S-, -(C=O)-, -(C=O)O-, -O(C=O)-, -(C=O)-NRe-, -(C=O)O-NRe-, or -O(C=O)-NRe-, wherein Re is one of hydrogen or a substituted or unsubstituted C1 to C6 hydrocarbon group,
R4 to R6 are independently one of hydrogen, a substituted or unsubstituted C1 to C20 alkyl
group, a substituted or unsubstituted C1 to C20 alkoxy group, a substituted or unsubstituted
C3 to C20 cycloalkyl group, a substituted or unsubstituted C6 to C20 aryl group, a
substituted or unsubstituted C3 to C20 heterocyclic group, a hydroxy group, a halogen,
a carboxyl group, or a combination thereof, provided that at least one of R4 to R6 is one of a substituted or unsubstituted C1 to C20 alkoxy group, a hydroxy group,
a halogen, or a carboxyl group, and
R7 is hydrogen or a methyl group.
5. The light emitting composite of any of claims 1-4, wherein the three dimensional protection
structure is represented by Chemical Formula 3:
[Chemical Formula 3] (R
8R
9R
10SiO
1/2)
M1(R
11R
12SiO
2/2)
D1(R
13SiO
3/2)
T1(SiO
4/2)
Q1
wherein, in Chemical Formula 3,
R8 to R13 are independently one of hydrogen, a substituted or unsubstituted C1 to C30 alkyl
group, a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or
unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C7 to C30 arylalkyl
group, a substituted or unsubstituted C1 to C30 heteroalkyl group, a substituted or
unsubstituted C2 to C30 heterocycloalkyl group, a substituted or unsubstituted C2
to C30 alkenyl group, a substituted or unsubstituted C2 to C30 alkynyl group, a substituted
or unsubstituted C1 to C30 alkoxy group, a substituted or unsubstituted C2 to C30
epoxy group, a substituted or unsubstituted C1 to C30 carbonyl group, a substituted
or unsubstituted C1 to C30 carboxyl group, a substituted or unsubstituted amide group,
a hydroxyl group, a (meth)acrylate group, a nitrile group, or a combination thereof,
one of R13's comprises a linking point with the light emitting element bound by -C(=O)NRa- (wherein Ra is hydrogen or a substituted or unsubstituted C1 to C10 hydrocarbon group),
at least one of R8 to R13 comprises a polymerizable functional group,

and

6. The light emitting composite of any of claims 1-5, wherein the light emitting element
comprises one of a quantum dot, phosphor, or a combination thereof; and/or
wherein a particle diameter of the light emitting composite is at least two times
larger than that of the light emitting element.
7. A light emitting structure comprising:
a cured product of the light emitting composite of any of claims 1-6;
preferably wherein the light emitting structure has a weight loss of less than or
equal to 5% at 300 °C
8. The light emitting structure of claim 7, further comprising:
a cured product of an organometal compound, or
a cured product of the light emitting composite and an organometal compound;
preferably wherein the organometal compound comprises one of an aluminum compound,
a titanium compound, a zirconium compound, a hafnium compound, a magnesium compound,
a tin compound, or a combination thereof.
9. An optical sheet or electronic device comprising:
the light emitting structure of claims 7 or 8.
10. The electronic device of claim 9, wherein the electronic device a light source, and
a display panel on the light source.
11. The electronic device of claim 10, wherein the light emitting structure is included
in the light source.
12. The electronic device of claims 10 or 11, wherein
the display panel includes a color conversion layer that is supplied with first visible
light from the light source and emits second visible light in the same wavelength
as the first visible light or in a longer wavelength than the first visible light,
and
the light emitting structure is included in the color conversion layer.
13. The electronic device of claim 12, wherein
the first visible light is blue light, and
the second visible light is one of blue light, green light, red light, or a combination
thereof.
14. The electronic device of any of claims 10-13, further comprising:
an optical sheet between the light source and the display panel, and
wherein the light emitting structure is included in the optical sheet.
15. The electronic device of any of claims 9-14, wherein
the electronic device includes a first electrode and a second electrode facing each
other, and an emission layer between the first electrode and the second electrode,
and
the emission layer includes the light emitting structure.